Accepted papers to appear in an upcoming issue
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Eigensurfaces of Eigenmirrors
Sarah Rody, R. Perline, and Robert Hicks
Doc ID: 363526 Received 28 Mar 2019; Accepted 17 Jun 2019; Posted 17 Jun 2019 View: PDF
Abstract: Typically, if an observer gazes at a curved reflector, the objects in it will appear to be distorted. We showhere that for some mirrors there exist surfaces that do not appear distorted when viewed from a prescribedlocation. We call such mirrors eigenmirrors and the surfaces eigensurfaces. We first give an analysis of therotationally symmetric case and verify our work with simulations. In the general three-dimensional case,if the mirror is given, then one does not expect an eigensurface to exist. On the other hand, if we aregiven two viewpoints and a correspondence between the ray bundles emanating from each point, and wetreat both the eigenmirror and the eigensurface as unknowns, then the problem reduces to solving a firstorder nonlinear partial differential equation. We derive this partial differential equation in the 3D caseand examine one example in detail.
Coherence of radiation from incoherentsources: I. Sources on a sphere and far fieldconditions
Doc ID: 366459 Received 30 Apr 2019; Accepted 14 Jun 2019; Posted 17 Jun 2019 View: PDF
Abstract: Models for the coherence of quasi-monochromatic light from spherical incoherentsources are constructed by placing incoherent monopole and dipole sources on the surface of asphere. All models allow for relatively simple numerical calculations of coherence functionsfor arbitrary source sizes and positions of observation points. We show analytically andconfirm numerically that the far-field regime for transverse coherence is formed at distanceslarger than the source size, regardless of the wavelength.
On the validity domain of approximations to estimationvariance of polarization degree, azimuth and ellipticity
Francois Goudail and jun dai
Doc ID: 362521 Received 14 Mar 2019; Accepted 12 Jun 2019; Posted 13 Jun 2019 View: PDF
Abstract: We determine the validity domain of classical approximations to estimation variance of degree of polarization(DOP), angle of polarization (AOP), and ellipticity (EOP), when the measurement matrix of theStokes vector is a spherical 2 design and noise is additive, white and Gaussian. We demonstrate that thisdomain of validity is quite large, so that these approximations can be used safely for back-of-the-envelopecalculations. In the presence of strong noise, DOP and EOP approximations show however some limits.We thus derive other approximations with extended domain of validity that can account for the dependenceof DOP and EOP estimation variance on actual DOP and EOP values. The obtained results areimportant for design and performance characterization of polarimeters.
Sampling Below the Nyquist Density UsingSpectral Subtiles
Doc ID: 361668 Received 05 Mar 2019; Accepted 10 Jun 2019; Posted 11 Jun 2019 View: PDF
Abstract: An image is assumed to have a spectrum zerooutside of a defined support. To avoid aliasing, the replicatedsupport due to sampling cannot overlap. The minimum samplingdensity corresponding to nonoverlapping supports is the Nyquistdensity. Replication often necessitate gaps. Support shapesthat fill the frequency plane without gaps are tiles. We offera strategy for achieving minimum sampling density when thespectrum is confined to a subtile. Cookie cutter versions of thesubtile shape, when rotated, translated and/or flipped, result ina tile. The composite signal can have symmetric redundanciesthat allow reduction of the sampling density to the area ofthe subtile. We analyze the cases for tiles with twofold pointsymmetry and mirror symmetry. Two subtiles are required toconstruct a tile. Threefold, fourfold and sixfold symmetry is alsoconsidered. In the cases considered, the overall sampling densityin terms of the samples required storage is reduced to the areaof the support of the subtile.
Dual dynamically tunable plasmon-inducedtransparency in H-type graphene-based slow-lightmetamaterial
Enduo Gao, Zhimin Liu, Hongjian Li, Hui Xu, Zhenbin Zhang, Xiao Zhang, xin luo, Cuixiu Xiong, Chao Liu, Baihui Zhang, and Fengqi Zhou
Doc ID: 365544 Received 19 Apr 2019; Accepted 09 Jun 2019; Posted 10 Jun 2019 View: PDF
Abstract: An H-type-graphene-based slow-light metamaterial is proposed to produce a dual plasmon-induced transparencyphenomenon, which can be effectively modulated by Fermi level, carrier mobility of graphene and the mediumenvironment. The data calculated by coupled mode theory and results of numerical simulation show prominentagreement. In addition, both the simplicity and the continuity of the units of graphene-based metamaterial areextraordinary advantages. Furthermore, the slow-light characteristics of the proposed structure show that thegroup refractive index is as high as 7, which is more competitive than some other slow-light devices.
Off-axis average transmittance and beam spread ofpartially coherent flat-topped beam in turbulentunderwater medium
Aysan Keskin and Yahya Baykal
Doc ID: 361833 Received 07 Mar 2019; Accepted 08 Jun 2019; Posted 10 Jun 2019 View: PDF
Abstract: Effects of oceanic turbulence on the off-axis optical transmittance and beam spread are examined whenpartially coherent flat-topped beam wave propagates in underwater medium. To observe the oceanicturbulence effect, the power spectrum of homogeneous and isotropic oceanic water combining the effects ofsalinity and temperature is used. Employing the extended Huygens-Fresnel integral and Carter’s definitionfor the general beam formulation that is applied to partially coherent flat-topped beam, the effects of theparameters of power spectrum, the link on the off-axis average transmittance and beam spread are analyzed.The results obtained with the help of MATLAB program indicates that if the flatness of the optical beamincreases, the average transmittance increases and the beam spread decreases. Partial coherence is found tobe inversely proportional to the average transmittance, directly proportional to beam spread. Increase in thesource size is found to increase the average transmittance and to reduce the beam spread. Loss of the kineticenergy of fluid causes less turbulence. The rate of dissipation of kinetic energy per unit mass of fluid isdirectly proportional to the average transmittance while it is inversely proportional the beam spread. Therate of dissipation of the mean-squared temperature is inversely proportional to the average transmittanceand directly proportional the beam spread. When the temperature-induced optical turbulence is dominant,the average transmittance almost never decreases. However, the salinity-induced optical turbulence sharplyreduces the average transmittance, increases the beam spread of the partially coherent flat-topped beam inunderwater turbulence. When the off-axis parameter becomes larger, average transmittance decreases.
Spatio-angular fluorescence microscopyI. Basic theory
Talon Chandler, Hari Shroff, Rudolf Oldenbourg, and Patrick LaRiviere
Doc ID: 355705 Received 07 Jan 2019; Accepted 07 Jun 2019; Posted 07 Jun 2019 View: PDF
Abstract: We introduce the basic elements of a spatio-angular theory of fluorescencemicroscopy, providing a unified framework for analyzing systems that image single fluorescentdipoles and ensembles of overlapping dipoles that label biological molecules. We model anaplanatic microscope imaging an ensemble of fluorescent dipoles as a linear Hilbert-spaceoperator, and we show that the operator takes a particularly convenient form when expressed in abasis of complex exponentials and spherical harmonics—a form we call the dipole spatio-angulartransfer function. We discuss the implications of our analysis for all quantitative fluorescencemicroscopy studies and lay out a path towards a complete theory.
Spatio-angular fluorescence microscopyII. Paraxial 4f imaging
Talon Chandler, Hari Shroff, Rudolf Oldenbourg, and Patrick LaRiviere
Doc ID: 356883 Received 07 Jan 2019; Accepted 07 Jun 2019; Posted 07 Jun 2019 View: PDF
Abstract: We investigate the properties of a single-view fluorescence microscope in a 4 fgeometry when imaging fluorescent dipoles without using the monopole or scalar approximations.We show that this imaging system has a spatio-angular band limit, and we exploit the bandlimit to perform efficient simulations. Notably, we show that information about the out-ofplaneorientation of ensembles of in-focus fluorophores is recorded by paraxial fluorescencemicroscopes. Additionally, we show that the monopole approximation may cause biased estimatesof fluorophore concentrations, but these biases are small when the sample contains either manyrandomly oriented fluorophores in each resolvable volume or unconstrained rotating fluorophores.
The effect from collection range of bucket detector onghost imaging through turbulent atmosphere
Wei Tan, Xianwei Huang, Suqin Nan, Yanfeng Bai, and Xiquan Fu
Doc ID: 366118 Received 26 Apr 2019; Accepted 06 Jun 2019; Posted 06 Jun 2019 View: PDF
Abstract: A model of collection range of bucket detector is proposed to investigate ghost imaging through turbulentatmosphere. The influence of the collection range of bucket detector under different turbulence intensity on thequality of ghost imaging is discussed. The numerical results show that the quality of ghost imaging increases withan increment of the collection range of bucket detector and a decrease of the turbulence intensity. Specifically, wegive a critical collection range of bucket detector which is the minimum collection range for ghost imaging withdifferent turbulence intensity. Additionally, a comparison of ghost imaging through turbulent atmosphere withghost imaging through vacuum atmosphere is given to show the effect of turbulent atmosphere on ghost imaging.
Physical-optics propagation through curved surfaces
Rui Shi, Christian Hellmann, and Frank Wyrowski
Doc ID: 362327 Received 13 Mar 2019; Accepted 05 Jun 2019; Posted 05 Jun 2019 View: PDF
Abstract: Curved surfaces are the basic elements of various optical components and systems, such as microscopy systems,Diffractive Optical Elements (DOEs), freeform components, microlens arrays, etc. In order to modelthe propagation through curved surfaces fully vectorially and fast, the Local Plane Interface Approximation(LPIA) [Appl.Opt. 39, 3304–3313 (2000)] is often used. However, the evaluation of the validity and accuracy ofthis method has, to our knowledge, not yet been fully addressed in literature. In this work, we compare the fieldon the curved surface obtained by LPIA with that obtained with the Finite Element Method (FEM). We find itis highly accurate even when the size of the curved surface is of on the scale of microns. We further evaluate thelimitation of LPIA in the cases of multi-reflection/transmisson and internal resonance.
Diffractive Anisoplanatism and Tracker BandwidthLimitations
Scot Shaw and Erin Tomlinson
Doc ID: 362623 Received 18 Mar 2019; Accepted 02 Jun 2019; Posted 03 Jun 2019 View: PDF
Abstract: This work develops the concept of “diffractive anisoplanatism,” a phenomenon that limits tracker performancefor directed-energy applications by introducing differences between point-source-beacon tiltmeasurements and scoring-beam centroid motion. Our theoretical analysis of this phenomenon, checkedagainst wave-optics simulations, highlights two relevant effects: diffractive conversion of phase to amplitudein the beacon light, and diffractive spreading of the scoring beam into regions outside of the geometriccone sampled by the beacon. In this work, we derive expressions for the variance and power spectraldensity of the differential jitter between beacon tilt and scoring-beam centroid motion. Additionally, wefind a scenario-dependent frequency fS above which corrections of atmospheric tilt will increase, ratherthan decrease, scoring-beam centroid jitter on target. Diffractive anisoplanatism provides a fundamentalphysicslimit on tracker performance that should be considered alongside other practical limitations.
Analytic Propagation Variances and PSDs from aWave-Optics Perspective
Scot Shaw and Erin Tomlinson
Doc ID: 362612 Received 18 Mar 2019; Accepted 24 May 2019; Posted 28 May 2019 View: PDF
Abstract: This work presents an approach for constructing equations describing the effects of atmospheric turbulenceon propagating light, based on equations and concepts that will be familiar to those with a backgroundin paraxial wave-optics modeling. The approach is developed and demonstrated by workingthrough three examples of increasing complexity: the variance and power-spectral density (PSD) of theaperture-averaged phase gradient (G tilt) on a point-source beacon, the variance of the Zernike tilt differencebetween two physically separated point-source beacons, and the irradiance-weighted average phasegradient (centroid tilt) and target-plane jitter variance for a generic beam. The first two results are shownto be consistent with existing literature; the third is novel, and shown to agree with wave optics and to beconsistent with literature in the special case of a Gaussian beam.